There is no deadlier combination for resources developers than opposition from a joint front of environmentalists and First Nations.

In what appears to be a divide-and-conquer strategy, Prime Minister Stephen Harper named a special representative Tuesday to investigate first hand why First Nations in British Columbia are so opposed to energy infrastructure projects, including the controversial Northern Gateway pipeline.

The first would tie the Alberta oil sands to the West Coast, while the second would send bitumen to refineries on the American Gulf Coast.

Some of the chiefs brushed off the federal government’s appointment this week of a special envoy to look at tensions between natives and the energy industry.

Vancouver-based lawyer Doug Eyford is to focus on energy infrastructure in Western Canada, but some native leaders say he has no credibility.

He is to examine First Nations concerns about the troubled Northern Gateway proposal, as well as the development of liquid natural gas plants, marine terminals and other energy infrastructure in British Columbia and Alberta.

He will discuss environmental protection, jobs and economic development, and First Nations rights to a share of the wealth from natural resources.

Some native chiefs, however, said Eyford has already failed. Although he is also the federal government’s chief negotiator on comprehensive land claims, they said he hasn’t accomplished much on that file.

Chief Allan Adam of the Athabasca Chipewyan First Nation said natives are determined to block the pipelines.

“It’s going to be a long, hot summer,” he said at a news conference.

“We have a lot of issues at stake.”

Phil Lane Jr. of the American Yankton Sioux, said native groups south of the border will stand with their Canadian cousins.

“We’re going to stop these pipelines on way or another,” he said.

Chief Martin Louie of the Nadleh Whut’en First Nation in northern B.C., said the pipeline opponents will never back down.

“If we have to keep going to court, we’ll keep doing that,” he said.

He said the stakes are high and go beyond native issues.

“We’re the ones that’s going to save whatever we have left of this earth,” he said.

Chief Reuben George of the Tsleil-Waututh First Nation on Vancouver Island said it’s time to act against the federal government’s resource development agenda.

“We, as a nation, have to wake up,” he said. “We have to wake up to the crazy decisions that this government’s making to change the world in a negative way.”